Changing time zones on a Resmed 10 Elite?

[CB91710]

There is never any good reason to change times away from your home QTH.  

No, not ever.  

Use your machine when you sleep.  It doesn't care what the time is.  It is a CPAP, not a chronograph, not an alarm clock.  If you need to know what time it is, look at your wrist watch.

This.
Well...  actually...  if your sleep schedule is such that you generally sleep past noon, it will kick up to the next day and break the session.  It can be confusing on Sleepyhead.

You can "back up" to noon of the current date.
The issue of losing data is if you end up setting it back to during a time when you were logging... data logged after that time will be overwritten.

So say you sleep from 22:00 to 08:00
Tonight, at 22:00, you can set the machine back (from wherever it is) to 12:00
Your machine will log from 12:00 to 22:00.
Tomorrow, at 21:00, your machine will read 11:00, you don't want to overwrite data, but you can set the machine back to 01:00.
Go to bed at 22:00, your machine will log from 02:00 to 12:00.
The next night, before the machine kicks over to the next day at 20:00, you can back it up to the correct time any time after 13:00.
You won't lose data, but 2 or more days will be merged and appear to be one long sleep only broken by a couple of hours here and there.

I had to do this after, somehow, my machine got bumped ahead by 24 hours.
Adjusting for DST or time zone changes within the US does not pose a problem... but if I didn't live on the west coast, I wouldn't bother changing it on vacation.  With my "home" time zone on Pacific time, if I sleep past 9 it will split the session if I'm on Central time, but setting the clock "back" up to 5 hours is a non-issue as long as I do it before the machine kicks over to the next date.

Same for DST...  I could just set it to "standard" time and leave it alone, but I'm OCD that way and couldn't handle looking at Sleepyhead charts that are an hour off...  plus I'll often use the time on the charts to review some event that happened during the night, be it a dream that woke me up, or as with last weekend, a power outage that lasted 14 hours.

[CB91710]

NZDT is 5 hours ahead of China Standard Time, so you need to wait until the clock in your CPAP is past 17:00 at least. and you haven't used the machine in those past five hours. If you try to roll back past machine noon on any day with data recorded, it will tell you to wipe the data. Also you must do it before the machine's midnight, because you don't want to back up a whole day. - I made that mistake on a trip three time zones west.
Upon your return to NZ, you simply have to wait until China (machine) noon, and roll forward the five hours.

I think that will do it.

Oh ya...  You can probably do 5 hours in one session.

[CB91710]

My concern is that the data being reported is scrambled due to it being broken up into separate day reporting even though its just one sleep session which gives very unreliable and untrue AHI figures making reporting confusing at best.

Unless your DME/Insurance company is still monitoring you for compliance (this typically stops after 90 days), or you need compliance reports for DOT/FAA, that's really not a problem.

[ghce]

My concern is that the data being reported is scrambled due to it being broken up into separate day reporting even though its just one sleep session which gives very unreliable and untrue AHI figures making reporting confusing at best.

Unless your DME/Insurance company is still monitoring you for compliance (this typically stops after 90 days), or you need compliance reports for DOT/FAA, that's really not a problem.

I don't care about others monitoring my sleep data, it's for me that I want the data. 
Generally I tend to review my data monthly or as others have said after an a normal nights sleep.

[Sleeprider]

I do big timezone changes every couple of weeks, the data doesn't get scrambled, it sometimes appears to double count but actually doesn't - see attached. I leave well alone

Rob

Rob, just to be clear, you travel with your CPAP but do not change the clock to local time-zones? This looks like the approach I would advocate.